Ab Initio Design of Two-Photon Absorbing Materials

AbstractTwo-photon absorbing materials such as conjugated polyenes show promise as nonlinear optical materials. Prediction of two-photon absorption frequencies and cross-sections has been limited by the high level of ab initio calculations that must be carried out in order to accurately calculate excited state energies and transition dipole moments, by the size of many of the compounds of interest, and by the difficulty of handling condensed phase effects in the calculations. We have carried out geometry optimizations at the multi-configurational selfconsistent field level on a small polyene, hexatriene, both in the gas-phase and in solution, with the solvent effects being modeled by the effective fragment potential. The excited-state energies have been calculated by the multiconfigurational quasidegenerate perturbation theory. Transition dipole moment calculations have also been carried out, from which the two-photon absorption cross-section can be estimated. The results indicate that just one or two solvent molecules can have a large effect on the nonlinear optical properties of two-photon absorbing materials.

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THEORETICAL STUDIES OF ONE- AND TWO-PHOTON ABSORPTION PROPERTIES FOR SYMMETRIC MOLECULES BASED ON BIS(STILBENE)DIETHYLENE

Journal of Theoretical and Computational Chemistry ◽

10.1142/s0219633606002489 ◽

2006 ◽

Vol 05 (03) ◽

pp. 535-542 ◽

Cited By ~ 1

Author(s):

SHU-LAN ZHOU ◽

XIAN ZHAO ◽

XUE-QIN SUN ◽

XIU-FENG CHENG

Keyword(s):

Excited State ◽

Cross Sections ◽

Dipole Moments ◽

Photon Absorption ◽

Absorption Properties ◽

Final State ◽

Transition Dipole ◽

Two Photon Absorption ◽

Two Photon ◽

Acceptor Side

In order to investigate the substituting effects on the two-photon absorption (TPA) cross-section and the position of the TPA peak, the one- and two-photon absorption properties of a series of symmetric molecules with bis(stilbene)diethylene π-conjugated bridge have been studied using ZINDO-SOS method. The transition moments from the ground state to the lowest excited state (M0k) and from the lowest excited state to the TPA final state (Mkn), together with the detuning energy ΔE = E0k - Ekn/2, were calculated using the INDO1 method included in the ZINDO program. The results indicate that bis-donor and bis-acceptor substitutions mainly affect the transition dipole moments M0k and Mkn, and that donor or acceptor side groups have a strong influence on the detuning energy. Meanwhile, it was found that the molecules with the bis-donor structure possess enhanced TPA cross sections, and the molecules with cyano or methoxy side groups have a large red-shift with respect to molecules without side groups.

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Theoretical studies on the one- and two-photon absorption of tetrabenzoporphyrins and phthalocyanines

Canadian Journal of Chemistry ◽

10.1139/v03-175 ◽

2004 ◽

Vol 82 (1) ◽

pp. 19-26 ◽

Cited By ~ 16

Author(s):

Xin Zhou ◽

Ai-Min Ren ◽

Ji-Kang Feng ◽

Xiao-Juan Liu

Keyword(s):

Dipole Moment ◽

Cross Sections ◽

Density Functional ◽

Transition Dipole Moment ◽

Photon Absorption ◽

Transition Dipole ◽

Two Photon Absorption ◽

Two Photon ◽

Order Of Magnitude ◽

The One

The one-photon absorption (OPA) properties of tetrabenzoporphyrins (TBPs) and phthalocyanines (Pcs) were studied using the semiempirical ZINDO method and time-dependent density functional theory (TDDFT), respectively. The compared results confirmed that the semiempirical ZINDO method was reasonably reliable when calculating the OPA of tetrabenzoporphyrins and phthalocyanines. On the basis of the OPA properties obtained from the ZINDO method, two-photon absorption (TPA) properties of two series of molecules were investigated, using ZINDO and sum-over-states (SOS) methods. The results showed that the TPA cross-sections of all molecules were in the range of 220.6 × 1050 345.9 × 1050 cm4·s·photon1, which were in the same order of magnitude as the values reported in the literature. The relatively larger δ(ω) value for Pcs with respect to that for corresponding TBPs originates from larger intramolecular charge transfer, which can be characterized by the difference of dipole moment between S0 and S1 and the transition dipole moment between S1 and S5.Key words: two-photon absorption, ZINDO, sum-over-states, tetrabenzoporphyrin, phthalocyanines.

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Studies on the two-photon absorption properties of trigonal dehydrobenzo[18]annulenes

Canadian Journal of Chemistry ◽

10.1139/v04-086 ◽

2004 ◽

Vol 82 (7) ◽

pp. 1172-1178 ◽

Cited By ~ 4

Author(s):

Xin Zhou ◽

Ai-Min Ren ◽

Ji-Kang Feng ◽

Xiao-Juan Liu

Keyword(s):

Dipole Moment ◽

Cross Section ◽

Intermediate State ◽

Density Functional ◽

Transition Dipole Moment ◽

Photon Absorption ◽

Absorption Properties ◽

Transition Dipole ◽

Two Photon Absorption ◽

Two Photon

The one-photon and two-photon absorption properties of donoracceptor substituted dehydrobenzo[18]annulenes were determined by using density functional theory and ZINDO methods. The macrocycle containing C2v symmetry exhibited the largest TPA cross-section value of 3376 × 1050 cm4 s/photon. The calculated results indicate that the TPA response in the whole molecule comes from the contribution of that in the every side in the trigon. It is notable that the magnitudes of the transition dipole moment from the virtual intermediate state to the TPA final state and the dipole moment difference between the ground state and the virtual intermediate state play important roles in increasing the TPA cross-section value. This series of molecules can circumvent the trade-off between efficiency and transparency, and they provide a promising direction for the further development of novel two-dimensional molecules with such properties.Key words: two-photon absorption, ZINDO, sum-over-states, dehydrobenzo[18] annulenes, transparency.

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